feat: use BaggageContext to get and propagate context (#31)

* feat: use BaggageContext to get and propagate context

Closes #23
Affects #19

* docs: update documentation

Documentation/Reference/README.md

@@ -29,6 +29,7 @@
 
 ## Extensions
 
+-   [BaggageContext](extensions/BaggageContext.md)
 -   [XRayRecorder](extensions/XRayRecorder.md)
 -   [XRayRecorder.Segment](extensions/XRayRecorder.Segment.md)
 -   [XRayRecorder.Segment.Cause](extensions/XRayRecorder.Segment.Cause.md)
@@ -42,4 +43,4 @@
 -   [Encoder.OutboundOut](typealiases/Encoder.OutboundOut.md)
 -   [Segment.Metadata](typealiases/Segment.Metadata.md)
 
-This file was generated by [SourceDocs](https://github.com/eneko/SourceDocs) on 2020-07-24 15:43:16 +0000
+This file was generated by [SourceDocs](https://github.com/eneko/SourceDocs) on 2020-07-25 06:07:01 +0000

Documentation/Reference/classes/XRayRecorder.Segment.md

@@ -13,20 +13,12 @@ At a minimum, a segment records the name, ID, start time, trace ID, and end time
 - [AWS X-Ray segment documents](https://docs.aws.amazon.com/xray/latest/devguide/xray-api-segmentdocuments.html)
 
 ## Properties
-### `context`
+### `baggage`
 
 ```swift
-public var context: TraceContext
+public var baggage: BaggageContext
 ```
 
-### `id`
-
-```swift
-public var id: ID
-```
-
-A 64-bit identifier for the segment, unique among segments in the same trace, in **16 hexadecimal digits**.
-
 ### `name`
 
 ```swift

Documentation/Reference/classes/XRayRecorder.md

@@ -17,27 +17,50 @@ public class XRayRecorder
 public init(emitter: XRayEmitter, config: Config = Config())
 ```
 
-### `beginSegment(name:parentId:aws:metadata:)`
+### `beginSegment(name:context:metadata:)`
 
 ```swift
-public func beginSegment(name: String, parentId: Segment.ID? = nil,
-                         aws: Segment.AWS? = nil, metadata: Segment.Metadata? = nil) -> Segment
+public func beginSegment(name: String, context: TraceContext, metadata: Segment.Metadata? = nil) -> Segment
 ```
 
-### `beginSubsegment(name:parentId:aws:metadata:)`
+Creates new segment.
+- Parameters:
+  - name: segment name
+  - context: the trace context
+  - metadata: segment metadata
+- Returns: new segment
 
-```swift
-public func beginSubsegment(name: String, parentId: Segment.ID,
-                            aws: Segment.AWS? = nil, metadata: Segment.Metadata? = nil) -> Segment
-```
+#### Parameters
+
+| Name | Description |
+| ---- | ----------- |
+| name | segment name |
+| context | the trace context |
+| metadata | segment metadata |
 
-### `beginSegment(name:context:aws:metadata:)`
+### `beginSegment(name:baggage:metadata:)`
 
 ```swift
-public func beginSegment(name: String, context: TraceContext,
-                         aws: Segment.AWS? = nil, metadata: Segment.Metadata? = nil) -> Segment
+public func beginSegment(name: String, baggage: BaggageContext, metadata: Segment.Metadata? = nil) -> XRayRecorder.Segment
 ```
 
+Creates new segment.
+Extracts the thre context from the baggage.
+Creates new if the baggage does not contain a valid XRay Trace Context.
+- Parameters:
+  - name: segment name
+  - baggage: baggage with the trace context
+  - metadata: segment metadata
+- Returns: new segment
+
+#### Parameters
+
+| Name | Description |
+| ---- | ----------- |
+| name | segment name |
+| baggage | baggage with the trace context |
+| metadata | segment metadata |
+
 ### `wait(_:)`
 
 ```swift

Documentation/Reference/extensions/BaggageContext.md

@@ -0,0 +1,15 @@
+**EXTENSION**
+
+# `BaggageContext`
+```swift
+public extension BaggageContext
+```
+
+## Properties
+### `xRayContext`
+
+```swift
+var xRayContext: XRayRecorder.TraceContext?
+```
+
+XRay Trace Context..

Documentation/Reference/extensions/XRayRecorder.md

@@ -6,18 +6,18 @@ extension XRayRecorder
 ```
 
 ## Methods
-### `segment(name:parentId:metadata:body:)`
+### `segment(name:context:metadata:body:)`
 
 ```swift
-public func segment<T>(name: String, parentId: Segment.ID? = nil, metadata: XRayRecorder.Segment.Metadata? = nil,
+public func segment<T>(name: String, context: TraceContext, metadata: XRayRecorder.Segment.Metadata? = nil,
                        body: (Segment) throws -> T)
     rethrows -> T
 ```
 
-### `segment(name:traceHeader:metadata:body:)`
+### `segment(name:baggage:metadata:body:)`
 
 ```swift
-public func segment<T>(name: String, traceHeader: TraceContext, metadata: XRayRecorder.Segment.Metadata? = nil,
+public func segment<T>(name: String, baggage: BaggageContext, metadata: XRayRecorder.Segment.Metadata? = nil,
                        body: (Segment) throws -> T)
     rethrows -> T
 ```
@@ -34,16 +34,9 @@ public convenience init(config: Config = Config(), eventLoopGroup: EventLoopGrou
 public func flush(on eventLoop: EventLoop) -> EventLoopFuture<Void>
 ```
 
-### `segment(name:parentId:metadata:body:)`
+### `segment(name:context:metadata:body:)`
 
 ```swift
-public func segment<T>(name: String, parentId: Segment.ID? = nil, metadata: Segment.Metadata? = nil,
+public func segment<T>(name: String, context: TraceContext, metadata: Segment.Metadata? = nil,
                        body: () -> EventLoopFuture<T>) -> EventLoopFuture<T>
 ```
-
-### `beginSegment(name:parentId:metadata:body:)`
-
-```swift
-public func beginSegment<T>(name: String, parentId: Segment.ID? = nil, metadata: Segment.Metadata? = nil,
-                            body: (Segment) -> EventLoopFuture<T>) -> EventLoopFuture<(Segment, T)>
-```

Documentation/Reference/structs/XRayRecorder.TraceContext.md

@@ -6,6 +6,9 @@
 public struct TraceContext
 ```
 
+XRay Trace Context propagated in a tracing header.
+
+# Tracing header
 All requests are traced, up to a configurable minimum.
 After reaching that minimum, a percentage of requests are traced to avoid unnecessary cost.
 The sampling decision and trace ID are added to HTTP requests in **tracing headers** named `X-Amzn-Trace-Id`.
@@ -46,15 +49,15 @@ root trace ID
 ### `parentId`
 
 ```swift
-public let parentId: Segment.ID?
+public var parentId: Segment.ID?
 ```
 
 parent segment ID
 
 ### `sampled`
 
 ```swift
-public let sampled: XRayRecorder.SampleDecision
+public var sampled: XRayRecorder.SampleDecision
 ```
 
 sampling decision
@@ -63,7 +66,7 @@ sampling decision
 ### `init(traceId:parentId:sampled:)`
 
 ```swift
-public init(traceId: XRayRecorder.TraceID = .init(), parentId: XRayRecorder.Segment.ID? = nil, sampled: XRayRecorder.SampleDecision)
+public init(traceId: XRayRecorder.TraceID = .init(), parentId: XRayRecorder.Segment.ID? = nil, sampled: XRayRecorder.SampleDecision = .sampled)
 ```
 
 Creates new Trace Context.

Examples/Package.swift

@@ -29,7 +29,6 @@ let package = Package(
             name: "AWSXRayRecorderExampleSDK",
             dependencies: [
                 .product(name: "AWSXRayRecorder", package: "aws-xray-sdk-swift"),
-                .product(name: "AWSXRayRecorderSDK", package: "aws-xray-sdk-swift"),
                 .product(name: "AsyncHTTPClient", package: "async-http-client"),
                 .product(name: "AWSS3", package: "aws-sdk-swift"),
             ]

Examples/Sources/AWSXRayRecorderExample/main.swift

@@ -22,8 +22,10 @@ enum ExampleError: Error {
 
 let recorder = XRayRecorder()
 
+let context = XRayRecorder.TraceContext()
+
 // begin and end (sub)segments explicitly
-let segment = recorder.beginSegment(name: "Segment 1")
+let segment = recorder.beginSegment(name: "Segment 1", context: context)
 segment.setAnnotation(98101, forKey: "zip_code")
 segment.setMetadata(["debug": ["test": "Metadata string"]])
 _ = segment.beginSubsegment(name: "Subsegment 1.1 in progress")
@@ -40,7 +42,7 @@ usleep(100_000)
 subsegment.end()
 
 // use closures for convenience
-recorder.segment(name: "Segment 2") { segment in
+recorder.segment(name: "Segment 2", context: context) { segment in
     try? segment.subsegment(name: "Subsegment 2.1") { segment in
         _ = segment.subsegment(name: "Subsegment 2.1.1 with Result") { _ -> String in
             usleep(100_000)

Examples/Sources/AWSXRayRecorderExampleSDK/main.swift

@@ -14,7 +14,6 @@
 import AsyncHTTPClient
 import AWSS3
 import AWSXRayRecorder
-import AWSXRayRecorderSDK
 import NIO
 
 func env(_ name: String) -> String? {
@@ -46,10 +45,10 @@ let recorder = XRayRecorder(
     eventLoopGroup: group
 )
 
-// TODO: WIP
+// TODO: WIP https://github.com/pokryfka/aws-xray-sdk-swift/issues/19
 
 let awsClient = AWSClient(
-    middlewares: [XRayMiddleware(recorder: recorder, name: "S3")],
+    //    middlewares: [XRayMiddleware(recorder: recorder, name: "S3")],
     httpClientProvider: .shared(httpClient)
 )
 let s3 = S3(client: awsClient)

Package.swift

@@ -10,13 +10,12 @@ let package = Package(
     products: [
         .library(name: "AWSXRayRecorder", targets: ["AWSXRayRecorder"]),
         .library(name: "AWSXRayRecorderLambda", targets: ["AWSXRayRecorderLambda"]),
-        .library(name: "AWSXRayRecorderSDK", targets: ["AWSXRayRecorderSDK"]),
     ],
     dependencies: [
         .package(url: "https://github.com/apple/swift-nio.git", .upToNextMajor(from: "2.17.0")),
         .package(url: "https://github.com/apple/swift-log.git", .upToNextMajor(from: "1.0.0")),
         .package(url: "https://github.com/Flight-School/AnyCodable.git", .upToNextMajor(from: "0.3.0")),
-        .package(url: "https://github.com/swift-aws/aws-sdk-swift-core.git", .upToNextMinor(from: "5.0.0-alpha.5")),
+        .package(name: "swift-baggage-context", url: "https://github.com/slashmo/gsoc-swift-baggage-context.git", .upToNextMinor(from: "0.1.0")),
         .package(url: "https://github.com/swift-server/swift-aws-lambda-runtime.git", .upToNextMajor(from: "0.2.0")),
     ],
     targets: [
@@ -26,6 +25,7 @@ let package = Package(
                 .product(name: "NIO", package: "swift-nio"),
                 .product(name: "Logging", package: "swift-log"),
                 .product(name: "AnyCodable", package: "AnyCodable"),
+                .product(name: "Baggage", package: "swift-baggage-context"),
             ]
         ),
         .target(
@@ -35,13 +35,6 @@ let package = Package(
                 .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
             ]
         ),
-        .target(
-            name: "AWSXRayRecorderSDK",
-            dependencies: [
-                .byName(name: "AWSXRayRecorder"),
-                .product(name: "AWSSDKSwiftCore", package: "aws-sdk-swift-core"),
-            ]
-        ),
         .testTarget(
             name: "AWSXRayRecorderTests",
             dependencies: ["AWSXRayRecorder"]

Sources/AWSXRayRecorder/Baggage.swift

@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the aws-xray-sdk-swift open source project
+//
+// Copyright (c) 2020 pokryfka and the aws-xray-sdk-swift project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import Baggage
+
+private enum XRayContextKey: BaggageContextKey {
+    typealias Value = XRayRecorder.TraceContext
+    var name: String { "XRayTraceContext" }
+}
+
+public extension BaggageContext {
+    /// XRay Trace Context..
+    var xRayContext: XRayRecorder.TraceContext? {
+        get {
+            self[XRayContextKey.self]
+        }
+        set {
+            self[XRayContextKey.self] = newValue
+        }
+    }
+}
+
+internal extension BaggageContext {
+    func withParent(_ parentId: XRayRecorder.Segment.ID) throws -> BaggageContext {
+        guard var context = xRayContext else { throw XRayRecorder.TraceError.missingContext }
+        context.parentId = parentId
+        var updated = self
+        updated.xRayContext = context
+        return updated
+    }
+}

Sources/AWSXRayRecorder/Recorder+Helpers.swift

@@ -11,14 +11,16 @@
 //
 //===----------------------------------------------------------------------===//
 
+import Baggage
+
 extension XRayRecorder {
     @inlinable
     @discardableResult
-    public func segment<T>(name: String, parentId: Segment.ID? = nil, metadata: XRayRecorder.Segment.Metadata? = nil,
+    public func segment<T>(name: String, context: TraceContext, metadata: XRayRecorder.Segment.Metadata? = nil,
                            body: (Segment) throws -> T)
         rethrows -> T
     {
-        let segment = beginSegment(name: name, parentId: parentId, metadata: metadata)
+        let segment = beginSegment(name: name, context: context, metadata: metadata)
         defer {
             segment.end()
         }
@@ -32,11 +34,11 @@ extension XRayRecorder {
 
     @inlinable
     @discardableResult
-    public func segment<T>(name: String, traceHeader: TraceContext, metadata: XRayRecorder.Segment.Metadata? = nil,
+    public func segment<T>(name: String, baggage: BaggageContext, metadata: XRayRecorder.Segment.Metadata? = nil,
                            body: (Segment) throws -> T)
         rethrows -> T
     {
-        let segment = beginSegment(name: name, context: traceHeader, metadata: metadata)
+        let segment = beginSegment(name: name, baggage: baggage, metadata: metadata)
         defer {
             segment.end()
         }